1. Field of the Invention
This invention relates to a driving method which permits a device of Metal-Insulator-Metal (MIM) structure having an organic insulating layer to exhibit multi-value recordability.
2. Related Background Arts
In the prior art, concerning enlargement of capacity of memory device, in devices using an inorganic substance such as Si, etc., it has been investigated to make memory cells higher in density by contrivance of memory cell structure and constitution of the circuit, reduction in number of the constituent elements, etc. Also, as another means for effecting enlargement of capacity, there is multi-value recording by use of a CCD digital memory or a memory using the photochemical hole burning effect.
However, the devices using inorganic substances involve the problem that the substrate forming the device is limited, because the manufacturing process is complicated, and high temperature steps are included in the process. On the other hand, the memory using the photochemical hole burning effect requires extremely low temperature, resulting in the problem that great restrictions are incurred in practical application.